Warming temperatures are melting patches of ice that have been in place for thousands of years in the mountains of the Canadian High Arctic and in turn revealing a treasure trove of ancient hunting tools.

Ice patches result from layers of annual snow that, until recently, remained frozen all year. As Earth's temperature has warmed in recent decades due to the accumulation of heat-trapping greenhouse gases in the atmosphere, some of the ice patches have begun to melt away, sometimes revealing ancient artifacts to the surprise of archaeologists.

"We're just like children opening Christmas presents. I kind of pinch myself," said Tom Andrews, an archaeologist with the Prince of Wales Northern Heritage Centre in Yellowknife, Northern Territories, Canada, and lead researcher on the International Polar Year Ice Patch Study